This application relates to techniques and devices that manipulate an optical beam for various applications, including, among others, optical detection and imaging, optical switching, optical computation, and optical storage.
An optical beam can interact with a variety of materials in different material states (e.g., solid, liquid, or gaseous state) under proper conditions. Such interaction may produce an output optical signal through at least one of different optical processes, such as optical scattering, optical reflection, optical transmission, optical emission, optical fluorescence and others. Depending on the nature of the interaction and the application, a particular optical process, e.g., optical transmission, may be selected to produce the output optical signal. It may also be desirable to detect two or more different output optical signals from different processes. In general, the interaction can change one or more properties of the input optical beam. This change can be detected or measured by measuring the output optical signal.
This disclosure includes techniques based on configurational effects of at least one pair of parts with one nano-scale part in a nano-scale configuration to produce a plasmon-enhanced or quantum-confined optical response when subject to a small change in a relative geometrical configuration of the two parts.
A device according to one embodiment includes first and second parts in which at least one of the parts has a dimension less than one wavelength of an input optical signal. The first part is formed of a material that is responsive to the input optical signal to produce a resonance at or near the input wavelength. Such a resonance characteristic of nano-scale parts may be plasmon resonances when the first part is designed to exhibit an electric conductivity such as being formed of a metallic particle, or a quantum-confinement resonance when the first part is formed of one or more quantum dots of diverse materials. The second part is spaced from the first part by less than one wavelength of the input optical signal. These two parts are arranged to be movable relative to each other and to interact to change a property of an output optical signal produced from scattering the input optical signal as the relative geometric configuration between the two parts changes.